| 摘要 |
A converter for converting an input voltage (Ui) into an output voltage (U0). The converter has several modes of operation. The converter can, for example, operate in an up-conversion mode, a down-conversion mode, or a window conversion mode. The converter has at least one switch (S1 - S4) for controlling the converter so as to obtain a desired value of the output voltage (U0) in the up-conversion mode and in the down-conversion mode. This is achieved by changing the duty cycle of a binary signal (BS) which controls the switch (S1 - S4). The converter further includes means (DMNS) for detecting the duty cycle of the binary signal (BS). This duty cycle is compared with a reference duty cycle (RFDCCL). The result of this comparison is used for deciding whether or not to change over from the up-conversion mode (or the down-conversion mode) to the window conversion mode. In the window conversion mode each switch (S1 - S4) in the converter is permanently closed or open. In the window conversion mode the output voltage (U0) is roughly equal to the input voltage (Ui) . The converter remains in the window conversion mode as long as the output voltage (U0) is within a given voltage window (range). However, if the output voltage (U0) has become too low, the converter changes over from the window conversion mode to the up-conversion mode. In a similar way, the converter changes over from the window conversion mode to the down-conversion mode when the output voltage (U0) has become too high.
|
